Here we report a patient with a blow-out fracture of the orbital floor that was treated by an intraoral transmaxillary approach. This 38-year-old man suffered a sudden blow to the periorbital area, which caused prolapse of the orbital contents into the maxillary sinus. The modified Caldwell-Luc approach was used to repair the orbital blow-out fracture and the maxillary sinus during was packed with Frazin gauze for 7 days to prevent recurrence of the prolapse. This was an easy and minimally invasive technique for the management of a blow-out fracture of the orbital floor.